modeltest_ScrollCompressor

Information

Short Description :

This model describes a hermetic scroll compressor. The model involves a limited number of parameters physically meaningful. The model accounts for the supply heating-up and exhaust cooling down of the gas, an internal leakage, the internal compression ratio and the electromechanical losses. The model is the one proposed by Winandy et al. (2002). Information used to identify the parameters is extracted from Copeland's catalogue (ZR72KC-TFD)

Nomenclature :

A Area, m^2

AU Global heat transfer coefficient, W/K

c_p Specific heat, J/kg-K

corr Correction factor for the swept volume, -

d Diameter, m

h Specific enthalpy, J/kg

M_dot Mass flow rate , kg/s

NTU Number of transfer units,-

N_rot Rotational speed, rpm

p Pressure, Pa

Q_dot Thermal power, W

R Thermal resistance, K/W

r_p Pressure ratio,-

r_v_in Internal built-in volume ratio,-

s Specific entropy, J/kg-K

t Temperature, C

u Specific internal energy, J/kg

v Specific volume, m^3/kg

V_dot_s Swept volume, m^3/s

W_dot Electrical power, W

x quality,-

Greek symbols

alpha Proportionality factor for electro-mechanical losses proportional to the internal power

DELTAt Temperature difference, K

epsilon Efficiency,-

gamma Isentropic coefficient,-

m3h Cubic meters per hour

rho Density, kg m-3

Subscripts

amb Ambient

calc Calculated

cd Condenser

cp Compressor

crit Critic

ev Evaporator

ex Exhaust

ex2 Exhaust before cooling exhaust down

ex1 Exhaust before exhaust pressure drop

n Internal

in* Corrected internal

leak Leakage

loss Electro-mechanical losses

loss0 Constant electro-mechanical losses

man Manufacturer (in Figures)

n Nominal

oh Over-heating

r Refrigerant

s Isentropic

s Swept volume

sat Saturation

sc Sub-cooling

su Supply

su1 Supply after supply heating-up

su2 Supply after mixing with internal mixing

thr Throat

w Water, enveloppe

References :

[1] Winandy, E., C., Saavedra O., J., Lebrun (2002) Experimental analysis and simplified modelling of a hermetic scrol refrigeration compressor. Applied thermal Engineering 22, 107-120.

Disclaimer

the accuracy or reliability of information presented in this model is not guaranteed or warranted in any way. Every use of this model, for commercial purpose or not, incurs liability of the user only. this model is freely distributed and may not be sold or distributed for commercial purpose. the user is asked to cite his sources and the origin of this model.

!Help us improving this model : any feedback comment is very welcome

Date : January 2014

Authors: Sylvain Quoilin

University of Liège

Faculty of Applied Sciences

thermodynamics Laboratory

Campus of Sart-tilman, B49 (P33)

B-4000 LIEGE (BELGIUM)

Contact: squoilin@ulg.ac.be

website : www.labothap.ulg.ac.be

Parameters

Components